A recent survey in Great Britain determined over half of Christian’s surveyed do not believe or are not sure that Jesus died on the cross to forgive sin. Seventeen percent said they disagreed with the statement, “Jesus died on the cross and was resurrected at Easter so that you can be forgiven for your sins.”

Many evangelical Christians consider belief in the death and resurrection of Jesus to forgive sin is essential to Christianity. Outside of Catholicism, no Christian group recognizes any human authority to determine who is or is not Christian. There is no membership fee or initiation process. Someone can claim to be a McDonald’s employee, but unless he is actively working for and receiving pay from McDonald’s corporation, the claim is obviously false. The same cannot be said of Christianity. One can go to church and have all the appearance of being a Christian without actually being one. Likewise, a genuine Christian can observe none of the outward trappings of Christianity and still be one.

The Bible defines who is a Christian. This is not determined by a committee decision, a council’s resolution, a church edict or a papal decree. The Bible defines what makes a person a Christian and describes the visible evidences of genuine Christianity. While no one has the authority to declare who is and is not a Christian, all believers have the ability- based upon the authority of Scripture- to declare that some who profess Christianity are not actually Christian.

Christianity is not determined by a strong feeling of being a Christian, nor even by doing Christian things. Jesus warned there would be some who preached and did miracles in His name that would be cast into hell. In the day of judgment Jesus will say to them, “I never knew you.” Personal feelings, religiousness or devotion are not what makes a person a Christian. What makes a person a Christian is proper belief personally applied.

Proper belief is belief in the gospel. The substance of the gospel is defined in Corinthians 15. The truths of Jesus’ death, burial and resurrection for our sin must be believed to be saved. Likewise, the Bible declares if a person denies certain key doctrines, then that person is not a Christian, no matter what they may call themselves. These undeniable doctrines include salvation by grace through faith alone (Galatians 1:7-8) and the deity of Jesus (1 John 4:2-3).

The New Testament gives a clear definition of who is and is not truly a Christian. A Christian is a person which believes Jesus is God who died on the cross for sin and rose again. A Christian is one who then abandons all attempts at securing salvation for himself and places his full trust in Jesus to forgive his sin. This definition has not changed in the two thousand years since Jesus’ life. No one is a Christian merely because they identify as a Christian. Self-identification as a Christian does not make a person a child of God any more than self-identification as a walrus makes a person a grumpy pinniped. Only faith in Christ makes one a Christian.